摘要
目的观察噪声习服对豚鼠听力损伤防护效应的时程变化。方法20只雄性豚鼠随机分为噪声习服组（A组）和直接暴露组（B组）。A组动物在声压级为90 dB SPL（声压级）、中心频率为0.5 kHz的一个倍频程噪声下连续暴露10 d,每天6 h,休息5 d,然后与B组动物同时在105 dB的白噪声下连续暴露7 d,每天4 h。每天在强噪声暴露前、后测定两组动物的听觉脑干反应（ABRs）阈值。结果A组动物在接受低噪声暴露后产生了习服效应。强噪声暴露后,A组1-7 d的平均阈移逐渐增加,而B组的平均阈移则逐渐减少;除第7天时的6 kHz频率外,A组在各时点上的click和短纯音（4、6、8 kHz）的平均阈移均显著低于B组。结论噪声习服对强噪声暴露引起的听力损伤具有一定的保护作用,但随着时间的推移,这种作用逐渐减弱。
] Objective To explore the effect of sound conditioning on noise - induced hearing loss （NIHL） in guinea pigs. Methods Twenty male albino guinea pigs were equally randomized into 2 groups. The animals were either （ A ） ： exposed to conditioning noise of a 0. 5 kHz octave band （90 dB for 6 h/d for 10 days） followed by exposure to high level white noise （105 dB for 4 h/d for 7 days） 5 clays later; or （B） ： similarly exposed to the high level noise directly. The preventive effects of sound conditioning on NIHL were determined by comparing the threshold shifts of auditory brainstem responses （ABRs） after the exposure. Results After the low noise exposure, group A produced conditioning effect. And after the high level white noise exposure, the threshold shifts of group A were gradually increased while those of group B decreased. The threshold shifts of group A were significantly less than those of group B on all time point, except the 6 kHz of the day 7. Conclusion The treatment of conditioning noise results in preventive effects on NIHL, while the effects are gradually reduced overtime.
出处
《中国预防医学杂志》
CAS
2009年第5期336-338,共3页
Chinese Preventive Medicine
关键词
噪声习服
听力损伤
听觉脑干反应
时程
Sound conditioning
Hearing loss
Auditory brainstem responses
Time course
